Pore-Scale Modelling of Thermal and Solvent Mobilization of Bitumen and Upscaling to Reservoir Level
Date
2019-01-03
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
A major shortcoming of the existing numerical models for prediction of solvent performance in the reservoir is the unrealistic assumption of equilibrium, viz. the complete mixing of the injected solvent with oil under field conditions. In this study, a workflow is developed to capture mass transfer and solvent dissolution in porous media and upscaling of the same for application to a reservoir simulator. The aim is to address the mechanism of solvent dissolution of bitumen and the expected improvement in oil recovery when a solvent is injected with steam. To achieve this goal, mobilization of bitumen with solvent is investigated using analytical models, pore-scale modelling, and reservoir simulators. In the first step, an analytical model is developed to investigate the validity of the non-equilibrium assumption and investigate the performance of heat and mass transfer in bitumen mobilization. The analytical investigation confirmed time and scale dependency of mass transfer phenomena. Therefore, a pore-scale simulator is developed to investigate the performance of cold and heated solvent injection in porous media. The results of the pore-scale simulation confirmed the slow rate of mass transfer even for heated solvent injection. In the next step, the pore-scale results are upscaled to address time-dependency of the average concentration of solvent in the oleic phase for use in a reservoir simulator. In the last step, a thermal reservoir simulator is developed and validated with analytical and numerical models. The simulator developed in conjunction with upscaled mass transfer coefficients is used to model the non-equilibrium phenomena for ES-SAGD. Results show that ignoring the non-equilibrium phenomena will result in overestimating the solvent performance viz. higher calculated solvent concentration and hence greater viscosity reduction. The simulation results show a reduction of 20-25% in increased oil production compared to ES-SAGD with equilibrium assumption for 10 wt% butane injection with steam.
Description
Keywords
Pore-Scale, Reservoir Simulation, Non-Equilibrium, Solvent Assisted Recovery Processes, Heavy oil and Bitumen, Analytical and Numerical Modelling
Citation
Bayestehparvin, B. (2019). Pore-Scale Modelling of Thermal and Solvent Mobilization of Bitumen and Upscaling to Reservoir Level (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.